What happens if somebody doesn’t have the mental capacity when writing their will?
In order for a will to be considered valid, the testator (i.e. the person making the will) must have sufficient mental capacity at the time of making or altering their will.
The word "mental capability" is problematic because it is frequently contested. A recent case involved a father who, a few weeks before committing himself, had disinherited his daughter and given his whole wealth to charity.
On the grounds that the testator possessed the required mental ability to draught the will, the court decided in favour of the charity.
Testamentary capacity, or whether the testator was of sound mind at the time and date of drafting or amending the will, may be at the centre of such disagreements.
The will may be found void if it is determined that the testator, the person who created it, lacked the necessary mental capacity at the time of writing it or making changes to it.
The test for capacity to execute a will is based on case law and a testator must:
- understand the nature of making a will and its effects;
- understand the extent of the property of which they are disposing;
- be able to comprehend and appreciate the claims to which they ought to give effect.
- have no disorder of the mind that perverts their sense of right or prevents the exercise of their natural faculties in disposing of their property by will.Remember that challenging a will or defending a challenge can turn out to be quite expensive in terms of legal fees, so it’s important you fully understand the intricacies of any such challenge or defence like this.If you’re not sure, please feel free to reach out to us, where we’ll put you in contact with one of our consultants.

